17-bromo 9, 11-oxido steroid adducts



Patented Dec. 23, 1952 UNITED STATES ATET OFFICE 17-BR-OMO 9,11-OXIDO STEROID ADDUCTS corporation of Michigan No Drawing. Application September 22, 1950,

Serial No. 186,308

' 4 Claims.

The present invention relates to-adducts of 3 acyloxy 9,11 oxido 17 bromo -'5,7- pregnadien-20-ones with certain dienophilic acids, anhydrides, and esters, and to a process for the production thereof.

The compounds of the present invention may be represented by the'structural formula:

1 CH3 1 6:0 OH; I

* m .odg

wherein Ac is the residue of an organic carboxylic acid, especially those containing from one to eight carbon atoms, inclusive; and A is the adduct radical of a dienophile selected from the group consisting of maleic acid, maleic anhydride, and maleic acid diesters containing from one to eight carbon atoms, inclusive, in the esterifying group.

It is an object of the present invention to provide a novel group of compounds whichare useful in the preparation of steroid compounds containing an oxygen atom at carbon atom eleven. Another object of the invention is the provision of a process for the production of the novel compounds, adducts of 3-acyloxy-9,11-oxido-17- bromo-5,'7-pregnadien-20-ones. Other objects of the invention will become apparent hereinafter.

The compounds of the present invention, as previously stated, are useful in the preparation of steroid compounds having an oxygen atom attached to carbon atom eleven. Such compounds are of particular interest in the field of steroid research due to 'the biological activity of the cortical hormones and certain known derivatives thereof, which oxygenated steroids are known to have biological effects differing markedly from the unoxygenated steroids. It is, therefore, of importance to investigate the oxygenated derivatives of such adducts, particularly those oxygenated at carbon atom eleven, as well as to investigate the biological activity of the adducts themselves and their transformation products. The importance of such investigation is moreover emphasized by the acute shortage of adrenalcortical hormones, and the absence of any present suggestion for allevia- 2 tion of the said shortage except through organic synthesis.

Novel compounds of the present invention which are of particular interest are those com pounds of the above generic formula wherein AcO represents an ester of the B-hydroxy group with a carb oxylic acid containing up to and including eight carbon atoms. Among the acids which can be used are formic, acetic, propionic, butyric, valeric, hexanoic, heptanoic, octanoic, succinic, glutaric, cyclopentanoic, cyclohexanoic, benzoic, toluic, and the like. Preferred acids are the lower-aliphatic acids. The acids may also contain substituents, such as halo, alkyl, and methoxy, which are non-reactive under the reaction conditions employed. The adduct bridge (--A) in such compounds may be represented by the graphic formula:

wherein R represents hydrogen or the organic residue of an alcohol. Such esters include the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, lauryl, heptyl, octyl, cyclopentyl, cyclohexyl, benzyl, and the like esters. The esterifying radical may also contain non-reactive substituents, such as halo, alkoxy, or hydroxy, if desired.

formula:

which is representative of the maleic anhydride adduct.

The compounds of the invention are usually colorless crystalline solids. The acid and anhydride adducts are readily converted into diester adducts by esterification with conventional reagents such as the diazoalkanes [Wilds et al., J. Org. Chem. 13, 763 (1948)]. The dibasic acids may be converted into their corresponding anhydrides by heat.

The 3-acyl0xy-9,1l-oxido-l'I-bromo-Bfl pregnadien-20-one adducts of the present invention have the formula:

o= CH3 1 Br j AcO V wherein A and Ac have the values previously given. These compounds are prepared by the selective bromination of the corresponding 3- acyloxy-9,11-oxido 5,7 pregnadien-2O one adduct, to introduce a bromine atom thereinto at the 1'7 position, using about one mole of bromine, preferably a slight excess over one mole of bromine, per mole of starting steroid. The steroid is dissolved in acetic acid and a solution of the bromine in acetic acid is added portionwise thereto at a temperature between about zero and thirty degrees centigrade. The reaction proceeds rapidly after a short initial induction period, apparently being catalyzed by the first hydrogen bromide which forms. After all the bromine has reacted with the steroid, as indicated by loss of color in the solution, the 9,11-oxido 17-bromo adduct may be recovered by pouring the reaction a mixture into ice-water and filtering the crystalline maeria] therefrom. If desired, the cornpound may be recrystallized to obtain a more highly purified product.

The starting 3-acy1oXy-9,1l-oxido-5,7-pregwherein A and Ac have the values given previously.

The preparation of the starting 3-acyloxy-9,11- oxido-5,7-pregnadien-20-one adducts involves the oxidation of the corresponding 3-acyloxy-5,7,9 (11) -pregnatrien-20-one adduct using an organic peracid or concentrated hydrogen peroxide as the oxidant. Hydrogen peroxide is usually employed in the form of a twenty to ninety percent by weight aqueous solution, a thirty percent solution being preferred. The reaction is carried out by stirring the adduct and oxidant together, preferably in an organic medium which is non-reactive under the reaction conditions. Suitable media include chloroform, carbon tetrachloride, mixtures of ether and chloroform, glacial acetic acid, and many others. The ratio of oxygenfurnishing agent to steroid can be varied considerably within broad ranges. Ratios of up to twenty moles to one are operative, but ratios of from one to four moles per mole of steroid are preferred for attainment of optimum yields, the exact ratio being preferably varied inversely with the reaction time desired to be employed. The temperature of the mixture is usually maintained at from about zero degrees to about degrees centigrade for a suitable period, e. g., from about one-half to twenty-four hours, depending on the concentration of oxygen-furnishing agent, and the 9,11-oxido compound then isolated in any convenient manner, such as by volatilizing the reaction medium, extracting the residue with chloroform, filtering, volatilizing the chloroform, and recrystallizing the residue from an organic solvent, Alternatively, the compounds may be recovered by pouring the reaction product into water, filtering the solution, and drying the precipitate. The 9,11-oxido compound is usually obtained in a state of high purity after one or two recrystallizations. A convenient reaction medium when the oxidant is hydrogen peroxide is glacial acetic acid, and, when such is employed, the 9,11-oxido compound is separated readily by pouring the reaction product onto cracked ice to precipitate the 9,11-oxido compound, filtering, and recrystallizing the dried crude product, e. g., from ethyl acetate.

The 3 acyloxy 5,7,9(l1) pregnatrien 20- one adducts are conveniently prepared by the selective oxidation of an enol ester of an adduct of 3 acyloxybisnor 5,7,9(11) cholatrien "2 a1, represented by the formula:

ACO

wherein A and Ac have the values reviousiy given.

Adducts of 3,22 diacyloxybisnor 5,7,9(1l), 20(22)-cholatetraenes [22-enol esters of 3-acyloxybisnor-5,'7,9(1l)-cholatrien-22-als] are conveniently prepared by subjecting an adduct of a 3 acyloxybisnor 5,7,9(11) cholatrien 22 al, of the formula:

1 CHCHO CH3 wherein A and Ac have the values previously given, to the action of an acid anhydride or an acid halide in the presence of an alkaline salt of the acid. The starting adducts of 3-acyloxybisnor-5,7,9(llJ-cholatriemZZ-als can be prepared from adducts of 3-esters of dehydroergosterol by selective oxidation as described and claimed in the copending application Serial 111,100 of Robert H. Levin, filed August 18, 1949, and as more fully described hereinafter.

The 3-esters of dehydroergosterol, from which the 3 acyloxybisnor 5,7,9(11) cholatrien- 22-al adducts are prepared, can be synthesized in several ways starting with ergosterol. For example, ergosterol can be transformed to dehydroergosterol with mercuric acetate according to known methods [Windaus et al., Ann. 465, 157 (1928)] and the 3-hydroxy group of the dehydroergosterol acylated by known procedure. Alternatively the B-hydroxy group of ergosterol can be acylated prior to the preparation of the dehydro derivative, a procedure which is particularly preferred in the preparation of the 3-acetoxy derivative. The adducts of dehydroergos terol are then prepared by the addition of maleic anhydride or the like to dehydroergosterol or a 3-ester thereof according to known methods lHonigmann, Ann. 508, 89 (1934)]. The anhydrides can then be converted to their corresponding acids and esters if desired.

The ester group, when present in the 3=-position of dehydroergosterol, is for the purpose of protecting the 3-hydroxy group in subsequent chemical reactions. For this purpose any convenient ester of an organic carboxylic acid, which is non-reactive under the conditions of the reaction, is suitable. The preferred acids are the fatty acids such as formic, acetic, propionic, butyric, valeric, hexanoic, heptanoic, octanoic; dibasic acids such as malonic, succinic, phthalic; cycloaliphatic acids such as cyclopentanoic and cyclohexanoic; and aromatic acids such as benzoic, toluic, and the like. The acids may also contain substitucnts such as halogen, alkyl, the methoxy radical, and the like, and these substituents will be carried throughout the synthesis. If desired, the acyl group can be changed to another acyl group by saponifying the ester to give a 3-hydroxy compound, which can then be reesterified as previously described.

A preferred method for preparing some of the dehydroergosteryl adducts comprises the saponification of a 3-acyloxy adducts of dehydroergosterol with dilute alkali followed by acidification. The 3-hydroxy dicarboxylic acid thus formed can be converted to the 3-hydroxy anhydride by heat, or it can be converted to any desired 3-acyloxy anhydride adduct by heating under reflux with the appropriate acid anhydride or chloride in pyridine solution. Dialkyl esters of the previously mentioned dicarboxylic acid adducts can be prepared by subjecting the acid to the action of an esterification reagent such as a diazoalkane [Wilds et al., J. Org. Chem. 13, 763 (1948) l, e. g., diazomethane, diazoethane, diazobutane, and the like.

The selective oxidation of an adduct of dehydroergosterol, or a 3-ester thereof, to produce an adduct of 3-hydroxybisnor-5,7,9(11) -cholatrien- 22-al, or a 3-ester thereof, is accomplished by dissolving the dehydroergosteryl adduct in a suitable solvent, cooling to about minus eighty to plus thirty degrees centigrade, and passing ozone into the solution until about 1.0 to 1.25 moles of ozone per mole of adduct have been absorbed. The temperature of the solution should be maintained below plus thirty degrees centigrade, preferably between a temperature of minus thirty and minus seventy degrees centigrade, during the addition of ozone, although temperatures as low as minus eighty and as high as plus thir 3: degrees centigrade are operative. The lower temperatures of the preferred range are readily obtained by cooling the solution of the adduct with a bath of solid carbon dioxide in acetone or the like, although various other methods of cooling can be used. Many of the customary solvents used in ozonizations such as chloroform, acetic acid, carbon tetrachloride, ethylene chloride, methylene chloride, and the like, can be used.

The ozonides are then decomposed under reducing conditions, that is, in the absence of oxidizing agents, whether added or formed in the course of the reaction by products of decomposition of the ozonide. This means that excess oxygen formed by decomposition of the ozonide is prevented from forming hydrogen peroxide by combining with any moisture present, and that molecular oxygen is prevented from oxidizing the aldehyde thus formed. This can be conveniently accomplished by decomposing the ozonide in glacial acetic acid by the addition of finelypowdered zinc.

As is conventional with ozonizations when conducted in solvents, other than glacial acetic acid. the solvent used for ozonization is replaced, after completion of the ozonization, by adding glacial acetic acid and removing the lower-boiling solvent by fractional distillation. Alternatively, the solvent can be removed by careful warming under reduced pressure prior to the addition of glacial acetic acid, if desired.

After decomposition of the ozonide and removal of the zinc, the aldehyde can be recovered by diluting the acetic acid with water, or in other conventional manner, such as by formation of an aldehyde derivative, e. g., the dinitrophenylhydrazone.

Adducts of 3,22 diacyloxybisnor 5,7,9(ll). 20(22) -cholatetraenes [22-en0l-esters of adducts of 3 acyloxybisnor-S,7,9(11) cholatrien-ZZ-alsl can be conveniently prepared by heating the corresponding 3-hydroxy or 3-acyloxy aldehyde maleic acid, maleic acid anhydride, or maleic acid ester adduct with a large excess of an organic carboxylic acid anhydride in the presence of a small amount of the alkali metal salt of the acid corresponding to the anhydride employed or an acid catalyst such as paratoluene sulfonic or sulfuric acid. The preferred anhydride is acetic anhydride, but other anhydrides, such as propionic, butyric, valeric, hexanoic, and octanoic anhydrides, as well as benzoic acid anhydride, orthotoluic acid anhydride, and the like, are also operative. The acid anhydrides can also be substituted by non-reactive groups, such as halo, alkyl, and methoxy, as in the case of chloroacetic, ortho-toluic, or methoxybenzoic acid anhydrides. The reaction can be conveniently fo1- lowed by observing the color changes in the reaction mixture, optimum yields being obtained by discontinuing the application of heat when the color of the solution changes from yellow to brown. Ordinarily the reaction is heated about degrees centigrade for from about four to six hours, but temperatures as low as 100 and as high as degrees centigrade are also operative. The reaction is usually conducted at the boiling point of the anhydride, but in the case of the higher-boiling anhydrides, such as benzoic anhydride, a suitable temperature control, as 100-150 degrees centigrade, must be used, since the adduct otherwise tends to decompose in the higher temperature range. If a E-hydroxy aldehyde adduct is thus reacted with an anhy dride, the hydroxy group will be acylated, and. similarly, if a maleic acid adduct is used instead of a diester or an anhydride, an anhydride will be formed. The enol ester can be isolated by removing the excess anhydride under reduced Pressure, and separating the enol ester from alkali metal salts, which procedure yields a product sufiiciently pure for most purposes, but which can be further purified by recrystallization from acetone-water, acetone-pentane, or like solvents, if desired.

The. ozonization of the thus-prepared enol acylate to produce a 3-acyloxy-5,7,9(1l)-pregnatrien-20-one adduct involves dissolving the enol ester in a suitable solvent, cooling to about minus eighty degrees centigrade to plus thirty degrees centigrade, and passing ozone, ozonized air, or ozonized oxygen into the solution until about 1.0 to about 1.25 moles, preferably 1.0 to 1.1 moles, of ozone per mole of adduct have been absorbed. The addition of ozone to the 20:22 double bond is so rapid that only a small amount of ozone escapes from the reaction mixture, and the amount of ozone ordinarily required therefore closely approximates the theoretical amount. Loss to the solvent, if any loss occurs, must be taken into consideration in caluculating the amount of ozone to be introduced. The ten perature of the solution should be maintained below plus thirty degrees centigrade, preferably between a temperature of minus thirty and minus seventy degress centigrade, during the addition of ozone, although temperatures as low as minus eighty and as high as plus thirty degrees centigrade are operative. peratures of the range are readily obtained by cooling the solution of the adduct with a bath of solid carbon dioxide in acetone or the like. although various other methods of cooling may be employed. Many of the customary solvents used in ozonizations, such as chloroform, methylene chloride, ethylene chloride, carbon tetrachloride, acetic acid, and the like, can be used for the ozonization reaction.

The 20:22 ozonides thus produced are then decomposed under conditions normally employed for decomposition of such compounds. This can conveniently be accomplished by decomposing the ozonide with hydrogen peroxide, by hydrolysis, by treatment with zinc in glacial acetic acid, i

or by a catalytic amount of colloidal metal such as silver, platinum, or palladium in a solvent, such as glacial acetic acid, alcohol, or ethyl acetate, in which latter case reductive conditions, e. g., a hydrogen atmosphere, are also employed. The use of reductive conditions is well established in the art [Hill and Kelly, Organic Chemistry," page 53, The Blakiston Company, Philadelphia (1934) Church et al., J. Am. Chem. Soc. 56, 176 184 (1934) Gilman Organic Chemistry, second edition, page 636, John Wiley and Sons, New York (1943); Long, Chem. Reviews 27, 452-d54 (1940) 1.

As is conventional with decomposition of ozonides with zinc, when the ozonizations are conducted in solvents other than glacial acetic acid, the solvent used for the ozonization is replaced, after completion of the ozonization, by adding glacial acetic acid and removing the lower-boiling solvent by fractional distillation, or the solvent can be removed by careful warming under reduced pressure prior to the addition of acetic acid, if desired. After decomposition of the 20:22 ozonide and removal of the metal, the ketone can be recovered by diluting the acetic acid with water, or by other conventional procedure for the recovery of ketones, such as by formation of a carbonyl derivative, e. g., the 2,4:- dinitrophenylhydrazone. Recrystallization from The lower term acetone or the like results in a more highly purified ketone product.

The following examples are illustrative of the process and products of the present invention, but are not to be construed as limiting.

PREPARATION 1.DIMETHYL MALEATE An uc'r or DEHYDROERGOSTERYL BENZoATn To a solution of 21 grams of dimethyl maleate adduct of dehydroergosterol in 69 milliliters of warm pyridine was added 9.5 milliliters of henzoyl chloride. After standing at room temperature for fifteen minutes, the mixture was poured into 1400 milliliters of ice-Water and the solid removed by filtration, dried, and recrystallized from acetone. There was thus obtained 26.4 grams of dimethyl maleate adduct of dehydroergosteryl benzoate, melting at 203 to 205.5 degrees centigrade.

PREPARATION 2,DIMETHYL lrlALEA'rE ADDL'CI or DEHYDROERGOSTERYL ACETATE In a manner essentially that described in Preparation 1, the dimethyl maleate adduct of dehydroergosteryl acetate, melting at 177 to 179 degrees Centigrade, was prepared from the dimethyl maleate adduct of dehydroergosterol and acetyl chloride.

PREPARATION 3.Di.\nsrnrn MALEATE Aomor or DEHYDROERGOSTERYL FORMATE A solution of six grams of dimethyl maleate adduct of dehydroergosterol in fifty milliliters of 87 percent formic acid was heated under reflux for one hour, cooled, and the dimethyl maleate adduct of dehydroergosteryl formate filtered therefrom. Upon crystallization from acetone, the purified material melted at 177.5 to 178.5 degrees centigrade.

PREPARATION .-M.irmc .lon) Avbuc'r or Din-1rnnonncosrnron A solution of 2.0 grams of sodium hydroxide in twenty milliliter of water was added to a solution of 1.73 grams of the maleic anhydride adduct of dehydroergosteryl acetate (M. P. 230-232 degrees centigrade) in forty milliliters of dioxane. The mixture solidified, but dissolved on addition of 300 milliliters of water and heating to eighty degrees centigrade. After half an hour the solution was cooled and made acid with aqueous three normal hydrochloric acid, to give 1.61 grams of precipitate. On crystallization from a dioxanewater mixture, the maleic acid adduct of dehydrogrgosterol melted at -192 degrees centigra e.

PREPARATION 6.-\IALE o ANHYDRIDE humor or 1) nrcrA-AcEroxYBrsNoR-5,7,9 (11) -CI'IOL.-i'lRlEN-22-AL a solution of 5.35 grams of the maleic anhydride adduct of 3-beta-acetoxydehydroergosterol in 107 milliliters of methylene chloride was cooled to about minus seventy degrees centigrade and czonized until 505 milligrams of ozone had been absorbed. The temperature of the solution was then gradually raised to about plus ten to fifteen degrees centigrade, whereupon seventy milliliters of glacial acetic acid was added and the methylene chloride removed under reduced pressure. Seven grams of zinc dust was then added to the cold solution at a uniform rate over a period of ten minutes, while keeping the reaction temperature below plus twenty degrees centigrade. After being stirred for fifteen minutes, the mixture was filtered and the filtrate poured into water. There was thus obtained 4.31 grams of maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11)-cholatrien-22-al, a fine white powder which melted at 187-197 degrees centigrade.

To a solution of 0.30 gram of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11)- cholatrien-22-al, in thirty milliliters of ethanol, was added twenty milliliters of alcohol containing one percent 2,4-dinitrophenylhydrazine and three percent concentrated hydrochloric acid. The mixture was allowed to stand for one hour at room temperature and then placed in a refrigerator to complete precipitation of the yellow crystals. The precipitate was then collected and recrystallized from a mixture of chloroform and alcohol, to give the 2,4-dinitrophenylhydrazone of the maleic anhydride adduct of B-beta-acetoxybisnor-5,7,9(11) -cholatrien-22al, melting at 269- 271 degrees centigrade.

PREPARATION 7.-MALEI ANHYDRIDE ADDUCT OF 3- BErA-AcEroxYBIsNon-5,7,9 (11) -CHOLATBIEN-22-AL A two-liter round-bottom flask was charged with fifty grams (0.93 mole) of dehydroergosteryl acetate maleic anhydride adduct and one liter of of acetic acid added, and the methylene chloride distilled over in vacuo at forty degrees centigrade or below. The flask was then placed in a water bath and fitted with a stirrer. An additional 200 milliliters of acetic acid was added and the ozonide decomposed by the addition of fifty grams of zinc dust. The zinc was added in portions over a period of twenty to thirty minutes while the solution was stirred and the temperature maintained at seventeen to twenty degrees centigrade. After addition, the mixture was stirred for another twenty minutes and then filtered. The precipitated zinc dust was washed by filtering 100 milliliters of acetic acid therethrough, and the filtrate gradually diluted with water (1100 to 1200 milliliters) until the product had been drowned out. The product was then cooled in the refrigerator overnight and filtered. The yield of crystalline product was 42 grams, assaying 89-95 percent of the desired aldehyde.

PREPARATION S In a manner essentially that described in 10 Preparation 6, the following compounds were prepared.

(l) Maleic anhydride adduct of 3-beta-formoxybisnor-5,7,9(11) -cholatrien-22-al, melting at -130 degrees centigrade. hydrazone, melting at -168 degrees centigrade.

(2) Maleic anhydride adduct of 3-beta-heptanoyloxybisnor-5,7,9 (11) -cholatrien-22-al, melting at 1975-19!) degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 253-257 degrees centigrade.

(3) Dimethyl maleate adduct of S-beta-benzoy1oxybisnor-5,7,9 (11) -cholatrien-22-al, meltin at 183-187 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 224-249 degrees centigrade.

(4) Dimethyl maleate adduct of B-beta-acetoxybisnor-5,7,9 (11) -cholatrien-22--al, melting at 172-178 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 238 to 244 degrees centigrade.

(5) Dimethyl maleate adduct of 3-hyd-roxybisnor-5,7,9(11) -cholatrien-22-al, melting at 163-170 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 250-254 degrees centigrade.

In a manner similar to the above, the maleic anhydride adduct of 3-hydroxybisnor-5,7,9(11)- cholatrien-22-al is obtained from dehydroergosteryl maleic anhydride adduct; the maleic acid adduct of 3-hydroxybisn-or-5,7,9(11)-cholatrien-22-al is obtained from dehydroergosteryl maleic acid adduct; and 3-acyloxybisn-or-5,7,9- (11)-cholatrien-22-almaleic acid adducts are obtained from the maleic acid adduct of 3-acyloxydehydroergosterols.

PREPARATION 9.-DIMETHYL MALEATE ADDUCT or 3-HYDRoxYBIsNoR-5,7 ,9 (11) -cHoLATnIEN-22-AL A solution of 2.69 grams (.005 mole) of the dimethyl ester of the maleic acid adduct of dehydroergosterol, in eighty milliliters of methylene chloride, cooled by a Dry-Ice and trichloroethylene bath, was treated with ozonized oxygen until 247.36 milligrams (.0051 mole) of ozone was absorbed. The solution was then allowed to warm to room temperature, whereafter thirty milliliters of acetic acid was added and the methylene chloride removed in vacuo. While cooling in a water-bath at fifteen degrees centigrade, four grams of zinc dust was added in portions with stirring, the temperature being maintained between fifteen and twenty degrees centigrade. Stirring was continued for another fifteen minutes, whereafter the zinc was separated by filtration. The filtrate was diluted with water to cloudiness, extracted with ether, the ether extract washed with sodium bicarbonate and then with water to neutrality, the solution then dried over sodium sulfate and evaporated to dryness in vacuo. The residue was crystallized from acetic acid and water, giving 1.92 grams (81.5 percent of the theoretical), melting point 91-97 degrees centigrade, which yielded a dinitrophenylhydrazone derivative in 72.5 percent yield, melting point 212-238 degrees centigrade. The aldehyde was recrystallized and found to have a purified melting point of 163-170 degrees centigrade, while the dinitrophenylhydrazone derivative was recrystallized until a melting point of 250-254 degrees centigrade was attained.

PREPARATION 10.MALEIc ANHYnR-IDE ADDUCI 0F 3- BETA-ACETOXY-22-ACETOXYBISNOR5,7,9 (11) ,20 (22) CHOLATETR-AENE A mixture of twenty grams of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11) 2,4-dinitrophenylcholatrien-22-al, six grams of anhydrous sodium acetate, and 600 milliliters of acetic anhydride, was heated under reflux for six hours, whereafter volatile components were removed under reduced pressure. The resulting solid was digested with five fifty-milliliter portions of boiling acetone for five minutes each, and the extracts combined and diluted with 130 milliliters of water. There was thus obtained sixteen grams of the maleic anhydride adduct of -3-beta-acetoxy-22-acetoxybisnor 5,7,9(11) ,20(22) cholatetraene, which melted at 186 to 193 degrees centigrade. Recrystallization of the crude product from a mixture of acetone and pentane raised the melting point to 200.5 to 202 degrees centigrade.

PREPARATIDN 11 In a manner essentially that described in Preparation 10, the following compounds were prepared:

(1) The dimethyl maleate adduct of 3-betabenzoyloxy 22- acetoxybisnor-5,7,9(11) ,20( 22) cholatetraene, which melted at 210 to 211 degrees centigrade.

(2) The dimethyl maleate adduct of 3-betaacetoxy 22- acetoxybisnor 5,7,9 (11) 20 (22) cholatetrae'ne, which melted at 181 to 183 degrees centigrade.

'In the same'manner as given above, 22-acyloxy, e. g., formoxy, acetoxy, propionoxy, butyroxy, valeroxy, hexanoyloxy, heptanoyloxy, octanoyloxy, benzoyloxy, and the like 3-acyl0xybisnor 5,7,9( 11) ,20(22) cholatetraene adducts, are obtained from the compounds of Preparations 6, 7, and 8. Such representative compounds include 3-formoxy-22-acetoxybisnor-5,7,9(11),- 20(22) -cholatetraene, 3-propionoxy-22-acetoxybisnor-5,7,9 ll) 20 (22) -cholatetraene, 3,22-dipropionoxybisnor 5,7,9(11),,20(22) cholatetraene, 3,22-dibenzoyloxybisnor 5,7,9 (11 ),20(22) cho latetraene, and 3heptanoyloxy-22-octanoyloxybisnor 5,7,9(11) ,20(22) cholatetraene adducts with maleic anhydride or maleic acid esters such as the dimethyl maleate, diethyl maleate, dipropyl-maleate, diisopropyl maleate, dibutyl maleate, dioctyl maleate, dibenzyl maleate, and the like;

Panrlmlyrlon 12.MALEI ANHYDRIDE Annuo'r or 3-BE1A=AoEroxY-5,7,9 (11") -1 nEGNATRIEN-2O-0Nn A solution of 5.03 grams of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11)- cholatrien-22-al enol acetate in 100 milliliters of methyl chloride was cooled to about minus seventy degrees centigrade and ozonized until 483 milligrams of ozone had been absorbed. Fifty milliliters of glacial acetic acid was then added and the methylene chloride removed under reduced pressure; An additional thirty milliliters of glacial acetic acid was then added and the ozonide decomposed by adding seven grams of powdered zinc at a substantially uniform rate while maintaining the reaction temperature between seventeen and twenty degrees centigrade. The mixture was stirred for an additional twenty minutes, filtered, and the zinc washed with 140 milliliters of glacial acetic acid. The organic extracts were combined and diluted with seventy milliliters of water. When crystallization commenced, the rate of precipitation was increased by addition of two volumes of water. There was thus obtained 4.0 grams of the maleic anhydride adduct of 3- beta acetoxy 5,7,9(11) pregnatrien one, which melted at 240 to 264.5 degrees centigrade. Several recrystallizations of the crude material 12 from acetone raised the melting point to 263.5 to 264.5 degrees centigrade.

l-nmnuexrron l3.MALE1o A011) Annual or 3-minl-Ifx'nROXY-5,7,9 (11) -IREGNAT1:lEN-QO-ONE A solution of 4.52 grams (0.01 mole) of the maleic anhydride adduct of 3-beta-acetoxy- 5,7,9(11) -pregnatrien-20-one, M. P. 263-2645 de grees centigrade, in a mixture of milliliters of lA-dioxane and 400 milliliters of water containing four grams (0.10 mole) of sodium hydroxide was allowed to stand at room temperature for two and one-half hours, whereupon a small quantity of plate-like crystals formed. These were dissolved by heating the mixture to seventy degrees centigrade for one-half hour. The reaction mixture was then made acid with fifty milliliters of three normal hydrochloric acid and refrigerated to give a precipitate of 3.05 grams of needle-like crystals melting at 173-177 degrees centigrade. On crystallization from a dioxanewater mixture, the compound melted at 211-215 degrees centigrade. The melting point was found to vary somewhat with the rate of heating.

PREPARATION 14.DnmrHYL MALEATE OF 3-BE'lA- HYDR XY-5,'Z ,9 (11) PREoNA RJErr-20pm:

A suspension of 0.4 gram of the maleic acid adduct of 3-beta-hydroxy-5,7,9(1l) -pregnatrien- 20-one, in fifty milliliters of dry ether, was cooled in an ice-salt bath while a slight excess of diazomethane in methylene chloride was added over a 25-minute period with stirring. Ten minutes after addition was complete, the solution was placed on a steam bath and concentrated rapidly to dryness. The residue was crystallized from an acetone-water mixture to give 0.34 gram of the dimethyl maleate of 3-beta-hydroxy-5,7,9(11)- pregnatrien-20-one, melting at 193-195 degrees centigrade. After chromatography and recrystallization, the compound melted at 192-197 degrees centigrade.

In the same manner as given above, other dialkyl maleates, e. g., the diethyl, dipropyl, diisopropyl, dibutyl, and dioctyl maleates 'of 3-hydroxy-5,7,9(11) -pregnatrien-'20-one are prepared from 3 hydroxy-5',7,9(1l)-pregnatrien-20 one maleic acidadduct and the appropriate'diazoalk'ane, or by other equivalent:esterification pro- PRETARATION 1,5.D1METHYL MALEATE 033-131511- Aonroxr-5 ,7,0 ll) -PREGNATRIEN-20-QNE A solution of 0.15 gram of, the dimethylmaleate adduct of 3-beta-hydroxy-5,7,9 (11) -pregnatrien- 20-one, in 2.5 milliliters of acetic anhydride and 2,5 milliliters of pyridine, was heated on the steam bath for ninety minutes, cooledto room temperature, and poured into ice-water. The resulting precipitate was collected by filtration and found to melt at 205-209 degrees centigrade. Recrystallization from methanol gave the dimethyl maleate of 3-beta-acetoxy5,7-,9 (1.1) -pregnatrien-20- one, melting at 207-211 degrees centigrade.

Analysis:

Calculated for C2eH3sO7 C 69.86; H 7.68 Found 69.81; 7.86 69.70; 7.62

By the same manner of. esterificaticn, the following C-3, esters were prepared: (1) dimethyl maleate adduct, of 3-beta-formoxy-5,7,9 11)- pregnatrien-ZO-one, melting point 223-230 degrees centigrade, and (2) the dimethyl maleate adduct of 3-beta-benzoyloxy-5,7,9(11)-pregnatrien-20-one, melting point 250-254 degrees centigrade.

PREPARATION 16.-MALEIO ANHYDBDJE Anouor or 3- BETA-HEPTANOYLOXY-5,7 ,9 (11) -PREGNATRIEN-20-ONE The maleic anhydride adduct of 3-betaheptanoyloxy 5,7,9(11 pregnatrien 20-one, melting point 170-171 degrees centigrade, was prepared by refluxing the maleic acid adduct of 3 beta hydroxy-5,7,9(11) -pregnatrien-20-one with heptylic anhydride and pyridine for a period of twenty hours, and working up the reaction product in the usual manner.

PREPARATION 17.l\fALEIo ANHYDRIDE Annoc'r OF 3-BETA-HYDROXY-5,7 ,9 (11) -1 nEcNArIiir2N-20-oNE Similarly, the maleic anhydride adduct of 3 beta-hydroxy 5,7,9(11) -pregnatrien-20-one, melting point about 195 degrees centigrade, was prepared by refluxing the maleic acid adduct of 3 beta hydroxy-5,7,9(11)-pregnatrien-20-one with Dowtherm for eight hours. The 3-hydroxy maleic anhydride adduct is also obtained by heating the 3-hydroxy maleic acid to just above its melting point, which procedure causes water to be evolved, with the closing of the anhydride ring.

PREPARATION 18.MALEIO ANHYDRIDE ADDUCT or 3- BETA-BENZO norm-5,7,9 (11) -PREcNA'rRIEN-20-oNn Seven and one-half grams of the maleic acid adduct of 3-beta-hydroxy-5,7,9(l1) -pregnatrien- 20-One (Preparation 13) was dissolved in ninety milliliters of pyridine and fifteen milliliters of benzoyl chloride was added thereto. The mixture was allowed to stand overnight at room temperature and was then poured into 1200 grams of crushed ice and water, resulting in formation of an oil which gradually solidified and was filtered off. The solid material was dissolved in acetone, treated with activated carbon, and crystallized from 125 milliliters of acetone diluted with 35 milliliters of water. This yielded 6.88 grams of 3-beta-benzoyloxy-5,7,9(1l -pregnatrien-ZO-One maleic anhydride adduct, melting point 219 to 224 degrees centigrade. Recrystallization from acetone resulted in a purer sample melting at 226.5 to 227.5 degrees centigrade.

In the same manner as given above, still other 5,7,9(11)-pregnatrien-20-one adducts are prepared from the corresponding 3,22-diacyloxybisnor 5,7,9(l1),20(22) cholatetraene maleic acid, maleic acid anhydride, and maleic acid diester adducts. Such compounds include the 3-formoxy-5,7,9(l1) pregnatrien 20 one maleic acid, maleic acid anhydride, dimethyl maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, diisopropyl maleate, dibenzyl maleate, and the like adducts; the corresponding S-propionoxy, butyroxy, valeroxy, hexanoyloxy, heptanoyloxy, octanoyloxy, benzoyloxy, and similar 20-ketone adducts, including, for example 3-propionoxy-5,7,9(ll) -pregnatrien-20-one dipropyl maleate, 3-benzoyloxy-5,7,9(l1)-pregnatrien-20-one dibenzyl maleate, 3-heptanoyloxy-5,7,9(11) pregnatrien-20-one dimethyl maleate, 3-valerOylOXy-5,7,9(11)-pregnatrien 20- one maleic acid anhydride adducts, and the like.

PREPARATION 19.DIMETHYL MALEATE ADDUo'r F 3- BETA-ACETOXY-Q,11-OXIDO-5,7PREGNADIEN--ONE One gram (0.002 mole) of the dimethyl maleate adduct of 3-beta-acetoxy-5,7,9(1l)pregnatrien-ZO-one was dissolved in milliliters of glacial acetic acid, and a solution of one milliliter of thirty percent hydrogen peroxide (four molar equivalents) in six milliliters of glacial acetic acid was added thereto at room temperature. The reaction mixture was heated on the steam bath for four hours, and thereafter allowed to stand at room temperature overnight. The mixture was then poured into 300 milliliters of water, the resulting precipitate separated by filtration. washed with water, and dried. The yield was 810 milligrams of the oxido compound melting at 197-206 degrees centigrade. After five recrystallizations from methanol and acetone-hexane, the dimethyl maleate adduct of 3 beta-acetoxy- 9,11 oxido 5,7 pregnadien-ZO-One melted at 216-221 degrees centigrade, [alpha]1:\ +11.4 degrees (in chloroform).

Analysis:

Per cent 0 Per cent I-I Calculated for Cz Hg O 67.68 7.44 Found 67.74: 7.35 68.02 7.49

PREPARATION 20.-MALEro ANHYDRIDE ADDUCT OF 3- BETA-ACETOXY-9,11-OXIDO-5,7-PREGNADIEN-20-0NE Five grams (0.011 mole) of the maleic anhydride adduct of 3-betaacetoxy-5,7,9(11)- pregnatrien-20-one was dissolved in 120 milliliters of hot glacial acetic acid, the solution thereafter cooled to room temperature, and a solution of five milliliters of thirty percent hydrogen peroxide (four molar equivalents) in thirty milliliters of glacial acetic acid added dropwise thereto with swirling. The reaction mixture was heated on the steam bath for three and one-half hours. The colorless solution was allowed to stand at room temperature overnight, poured into about one liter of water, the resulting precipitate separated by filtration, washed with water, and dried in a vacuum desiccator. The yield was 4.88 grams (94.8 percent), melting at 232-246 degrees centigrade. After two recrystallizations from acetone, crystals of the maleic anhydride adduct of 3-beta-acetoxy-9,l1- oxido-5,7-pregnadien-20-one, melting at 240-246 degrees centigrade, were obtained.

Analysis:

Per cent C Per cent H Calculated for C qHmO7 69.21 6.89 Found 69.43 6.94 69.30 6.97

PREPARATION 21.-MALEIO ANHYDRIDE ADDUCT on 3- BETA-AOETOXY-Q,ll-oxioo-5,7-I REeNAoIEN-20-oNE A solution of fifty grams of the maleic anhydride adduct of 3-beta-acetoxy-5,7,9(l1)- pregnatrien-20-one in 1200 milliliters of glacial acetic acid was prepared by heating the ingredients together on a steam bath. The mixture was then cooled below forty degrees centigrade and fifty milliliters of thirty percent hydrogen peroxide in 300 milliliters of glacial acetic acid added thereto. The mixture was then heated on the steam bath for one hour at a temperature of degrees Centigrade Or above, and was then poured into three to five volumes of ice and water. The yield was 47.7 grams (92 percent), melting point 238-243 degrees centi grade, [alphaln +3l.1 degrees in chloroform. The product was dissolved in methylene chloride and precipitated by addition of ether to give 37.7 grams of purified product having a melting point of 254 to 259 degrees centigrade. [alphalo -l-832 degrees (chloroform).

PREPARATION 22 In the same manner as given above for the preparation of 3-beta-acetoxy 9,11 oxido-5,7- pregnadien-20-one mal-eic anhydride adduct, the following compounds were prepared:

Analysis I Per cent C Per cent H Calculated for CQQIIMO'I 72.43' 6.46 Found 72.62 6.42 72.70 6.38

(2) Maleic anhydride adduct of B-heptanoylwry-9,11-oxido-5,7pregnadien-20-one, M. R168- 1695 degrees centigrade [alpha] +26.1 degrees (in chloroform).

Analysis Per cent C Per cent H Calculated for (732131410 71.48 7.69 Found 71.27 7.43

Other adducts of 3-acyloxy-9,11-0xido-5,7- pregnadien-ZQ-one include 3-propionoxy-9,11 oxido-5,7-pregnadien-20-one maleic acid adduct, 3-butyroXy-9,11-oXido-5,'7 pregnadien 2'0 one maleic anhydride adduct. 3-formoxy-9,11-oxido- 5,7-pregnadien-20-one dimethyl maleate adduct, 3-iorinoxy-9,11-oXido-5,7 pregnadien 20 one maleic anhydride adduct, 3-acetoXy-9,1 l-oxido- 5,7-pregnadien-20-one maleic acid adduct, 3- propionoxy-Q,11-oxido-5,7-pregnadien-20one diniethyl maleate adduct, 3-butyroxy-9,11-oxido- 5,7-pregnadien-20-one dimethyl maleate adduct, 3-octanoyloxy-9,1l-oxido 5,7 pregnadien 20- one dioctyl maleate adduct, 3-benz0yloxy-9,1l oxido-5,7-pregnadien-20-one maleic acid adduct, 3-propionoxy-9,11 oxido 5,7 pregnadien 20- one maleic anhydride adduct, and the like, which are repared in the same manner as given above, by epoxidation of the selected 9,1l-unsaturated starting compound.

Example L-Maleic anhydride adduct of 3-betaacez'oxy 9,11 oxid 17 bromo 5,7 pregnadien-Zi-one Ten grains of 3-beta-acet0xy-9,1l-oxido-5,7- pregnadien20-one maleic anhydride adduct was dissolved in 200 milliliters of acetic acid by warming and the solution then cooled to room temperature. Four milliliters of a bromine-acetic acid solution, having a 172 milligram'per milliliter concentration, was added and the mixture allowed to stand. After twenty minutes the bromine color had disappeared. An additional seventeen milliliters of bromine solution was then addedin portions as rapidly as the bromine wastaken up. The solution was allowed to stand for thirty minutes and was then poured into 1200 milliliters of Water. The resulting crystalline 3-beta-acetoxy- 9,11-oxido-17-bromo-5,7-pregnadien-20-one maleic anhydride adduct (11.6 grams,-melting point 19 4.96 degrees centigrade) was isolated by filtration. Recrystallization from acetone yielded material melting at 193-196 degrees centigrade, [9.12311313 of minus 1925 degrees in chloroform.

A nalysis Calculated [or C27H3107Bl' C, 59.23 H 5.71 B1: 14.60 Found 59.32' 6.21 14.71 59.20 6.46- 14.80

Example 2. Dimethyl maleate of 3-betaocetozy 9,11 oxide 17 bromo -'5,? pregmedian-204 9 To a solution of 355 milligrams of 3-betaacetoxy-9,11-oxido-17 bromo 5,7 pregnadien- 2fl-one maleic anhydride adduct in ten milliliters of methylene chloride and forty milliliters of methanol, cooled in an ice bath, was added fifty milliliters of a solution of diazomethane in methylene chloride in 25-milliliter portions,- fifteen minutes apart. The mixturewas allowed to stand in the ice bath for two hours and was then con centrated on the steam bath until crystallization began. After cooling and filtering, there was obtained 250 milligrams of crystalline 3-betaacetoxy 9,11-oxido-17-bromo 5,7 pregnadien- 20-one dimethyl maleate adduct which, after three recrystallizations from acetone-methylene chloride, melted at 239-2405 degrees centigrade, lalphalizr' of minus 34.3 degrees in chloroform.

Analysis:

Calculated for C H O BLJC, Found 58.68 H 6.28 Bl. 13.47 58.82 6.25 13.68 58.88 6.32 13.38

The same compound is prepared by the seventeen bromination of 3-beta-acetoXy-9,1l-oxido- 5,7-pregnadien-20-one dime'thyl maleate adduct, according to the method of the preceding example.

ExampZe'3.MaZeic anhydride adduct of 3-betabnzo'yZOacy-QJI-oxido 17 bromo 5,7 pregnadien-Zfl-one In exactly the same manner as given above in Example 1, the maleic anhydride adduct of 3- beta-benzoyloxy-Q,11-oXido-17-bromo-5,7- pregnadien-ZO-one is prepared bybromination of 3- beta-benzoyloxy-9,1l-oxido-5,7- pregnadien 20- one maleic anhydride adduct, which is prepared as given in Preparation 22. Still other 3-acyl0xy- 17-bromo-9,11-0xido-5,7-pregnadien-20 one adducts which are prepared in the same manner as given above include the 3-betaacetoxy-9,11- oxido-17-bromo-5,7-pregnadien 20 one maleic acid adduct, as well as 3-formoxy, 3-propionoxy, 3-butyroxy, 3-valeroyloxy, 3-hexanoyloxy, 3-heptanoyloxy, B-benzoyloxy and 3-octanoyloxy-9,11- oxido-17-bromo-5,7-pregnadien 20 one maleic acid adducts, maleic anhydride adducts, dimethyl maleate, diethyl maleate, dipropyl maleate, diisopropyl maleate, dibutyl maleate, diamyl maleate, dihexyl maleate, diheptyl maleate, dibenzyl maleate and dioctyl maleate adducts, and the like.

These 9,11-oxido 17-bromo' adducts are converted readily into 16,17 dehydro compounds, of the formula:

wherein A and Ac have the values previously assigned. The 3-acyloxy-9,l1 oxido 5,7,16(17) pregnatrien-ZO-one adducts are prepared from the corresponding 17-brom compound by dehydrobromination, which is accomplished by heating the l7-bromo compound in pyridine, e. g-., at about reflux temperature, recovering the reaction product by quenching the reaction in ice-water or in other conventional manner, and crystallizing the desired 3-acyloxy'-9,1l-oxido- 5,7,16(17)-pregnatrien-20-one adduct from an organic solvent or solvent pairs, if desired. Representative values of AcO in the above formula include, for example, formoxy, acetoxy, propionoxy, butyroxy, valeroyloxy, hexanoyloxy, heptanoyloxy, benzoyloxy, octanoyloxy, and the like, while the radicals represented by A include those of maleic acid. maleic anhydride, and di- 17 methyl, diethyl, dipropyl, diisopropyl, dibutyl, diamyl, dihexyl, diheptyl, dibenzyl, and dioctyl maleates, and the like.

Example A.--Malez'c anhydnde adduct of 3-betaexcretory-9,11-o:ridc-5,?,16-pregnatrien-20-one A solution of 0.5 gram of 3-beta-acetoxy-l7- bromo-9,l1-oxido-pregnatrien-ZO-one maleic anhydride adduct in fifteen milliliters of pyridine was refluxed for one hour, cooled, and poured into fifty milliliters of ice-water. The resulting yellow solid (0.27 gram, melting point 265-275 degrees centigrade) was crystallized from acetone-hexane to give 183 milligrams of 3-betaacetoxy 9,11 oxido-5,7,16-pregnatrien-20-one maleic anhydride adduct, having a melting point of 267-272 degrees centigrade. Ultraviolet and infrared analysis showed the presence of the alpha,beta-unsaturated ketone system.

It is to be understood that the invention is not to be limited to the exact details of operation or exact compounds shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

We claim:

1. A 3-acyloxy-9,1l-oxido-17-bromo-5,7-pregnadien-ZO-one adduct of the formula:

CH2 I 18 wherein A0 is the residue of an unsubstituted organic monocarboxylic acid containing from one to eight carbon atoms, inclusive, and wherein A is the adduct radical of a dienophile selected from the group consisting of maleic acid, maleic anhydride, and lower-alkyl diesters of maleic acid wherein the esterifying groups contain from one to eight carbon atoms inclusive.

2. 3 acetoxy 9,11-oxido-17-bromo-5,7-pregnadien-ZO-one maleic anhydride adduct.

3. 3 acetoxy 9,11-oxido-17-bromo-5,7-pregnadien-20-one dimethyl maleate adduct.

4. A compound of claim 1, wherein A00 is the acetoxy group.

ROBERT H. LEVIN. A VERN MCINTOSH, JR. GEORGE B. SPERO.

REFERENCES CITED UNITED STATES PATENTS Name Date Marker Feb. 6, 1945 Number 

1. A 3-ACYLOXY-9,11-OXIDO-17-BROMO-5,7-PREGNADIENE-20-ONE ADDUCT OF THE FORMULA: 